diff --git a/docs/libs/gelly_guide.md b/docs/libs/gelly_guide.md
index 94434d156c066dfebf098c779519ce63e5526516..fa49dcececcd6730e6584139adfb1e4e14601cee 100644
--- a/docs/libs/gelly_guide.md
+++ b/docs/libs/gelly_guide.md
@@ -389,10 +389,12 @@ all aggregates globally once per superstep and makes them available in the next
* Broadcast Variables: DataSets can be added as [Broadcast Variables]({{site.baseurl}}/apis/programming_guide.html#broadcast-variables) to the `VertexUpdateFunction` and `MessagingFunction`, using the `addBroadcastSetForUpdateFunction()` and `addBroadcastSetForMessagingFunction()` methods, respectively.
* Number of Vertices: Accessing the total number of vertices within the iteration. This property can be set using the `setOptNumVertices()` method.
-The number of vertices can then be accessed in the vertex update function and in the messaging function using the `getNumberOfVertices()` method.
+The number of vertices can then be accessed in the vertex update function and in the messaging function using the `getNumberOfVertices()` method. If the option is not set in the configuration, this method will return -1.
* Degrees: Accessing the in/out degree for a vertex within an iteration. This property can be set using the `setOptDegrees()` method.
-The in/out degrees can then be accessed in the vertex update function and in the messaging function, per vertex using `vertex.getInDegree()` or `vertex.getOutDegree()`.
+The in/out degrees can then be accessed in the vertex update function and in the messaging function, per vertex using the `getInDegree()` and `getOutDegree()` methods.
+If the degrees option is not set in the configuration, these methods will return -1.
+
* Messaging Direction: By default, a vertex sends messages to its out-neighbors and updates its value based on messages received from its in-neighbors. This configuration option allows users to change the messaging direction to either `EdgeDirection.IN`, `EdgeDirection.OUT`, `EdgeDirection.ALL`. The messaging direction also dictates the update direction which would be `EdgeDirection.OUT`, `EdgeDirection.IN` and `EdgeDirection.ALL`, respectively. This property can be set using the `setDirection()` method.
@@ -453,7 +455,7 @@ The following example illustrates the usage of the degree as well as the number
Graph graph = ...
// configure the iteration
-IterationConfiguration parameters = new IterationConfiguration();
+VertexCentricConfiguration parameters = new VertexCentricConfiguration();
// set the number of vertices option to true
parameters.setOptNumVertices(true);
@@ -476,8 +478,8 @@ public static final class VertexUpdater {
public static final class Messenger {
...
- // decrement the number of out-degrees
- outDegree = vertex.getOutDegree() - 1;
+ // retrieve the vertex out-degree
+ outDegree = getOutDegree();
...
}
@@ -490,7 +492,7 @@ The following example illustrates the usage of the edge direction option. Vertic
Graph, Double> graph = ...
// configure the iteration
-IterationConfiguration parameters = new IterationConfiguration();
+VertexCentricConfiguration parameters = new VertexCentricConfiguration();
// set the messaging direction
parameters.setDirection(EdgeDirection.IN);